feat(tooltip): Delayed tooltip seems to not be showing up

[DethAriel]

Didn't see a bug for this.

See http://valor-software.com/ng2-bootstrap/#/tooltip , and find "delayed" link-like element there. When you hover over it, the tooltip is supposed to be shown in a second, whereas in fact it never shows up (in Chrome at least). Probably the issue relates to Zones, and the setTimeout should be run inside the injected component Zone.

[DethAriel]

As far as I can tell, this reproduces if you don't subscribe to the (tooltipStateChanged) event, e.g.

<a href="#" tooltipPopupDelay='1000' tooltip='appears with delay'>
  delayed
</a>

The above is taken from example page